Gotta find the datasheet for your particular panel. The source for the difference is the blown up t480s main-board and a multi-meter. Later I got my hands on a datasheet I was probably not supposed to have that confirmed that.
No Idea but I’d definitely beep out the ground pins first and even then the allowed input voltage may still be a lot lower than what an lcd panel is used to. I don’t think samsung changed the input voltage just to be assholes (not that they aren’t, they pulled a few very asshole moves lately but this might not be one of those), there is probably a technical reason for that.
I also don’t even know of anybody other than samsung making high res oled laptop panels but I have not really looked above 14" so there might be.